how do i find my airport extreme's ip address

Open Macintosh HD > Applications > Utilities > AirPort Utility

Click on the AirPort Extreme icon

If the AirPort Extreme is performing as the main router on the network, Info will be displayed about the Internet, or public IP address, and also the private LAN or local IP address of the AirPort Exreme.

If another device is performing as the main router on your network, only the local IP address of the AirPort Extreme will be displayed.

when I click on AirPort Utility it opens upandhas Other AirPort Base Stations (black screen with world showing with Internet under it then at bottom of page it has "no configured Airport Base Stations have beenf ound.

My office administrator is asking for the AirPort Address so she can put my computer in the system and I don't know where to find it. Help Please, all this is totally new to me.